Generally, a wire harness for automobiles is constituted by a bundle of a plurality of electrical wires. The electrical wires are complexly connected between a large number of connectors that are connected to respective electrical equipment, and are branched or connected at intermediate splices or splices for gathering ends.
Conventionally, when performing splicing by gathering ends of a plurality of electrical wires, insulating cover members at ends of the electrical wires are peeled off, so that wire cores are exposed, the exposed plurality of wire cores are welded to each other using a resistance welder or an ultrasonic welder, and, thus, a splice portion for gathering ends is formed. Then, in order to protect and insulate the formed splice portion for gathering ends, a protective cap made of insulating resin is placed on the splice portion for gathering ends, and the plurality of electrical wires are fixed in an overlapping manner to a tape winding tongue piece projecting from this protective cap by winding an adhesive tape therearound.
However, according to the above-described conventional structure for protecting a splice for gathering ends, a splice portion for gathering ends of a plurality of electrical wires is fixed to the tape winding tongue piece by winding an adhesive tape therearound, and, thus, the splice portion for gathering ends cannot be maintained at the center in the protective cap, but is fixed in a state of being shifted toward the tape winding tongue piece. Thus, vibrations and impacts applied to the protective cap are easily transmitted to the splice portion for gathering ends inside the cap, and the wire cores may be separated due to damage on the welding of the splice portion for gathering ends depending on the size of the vibrations or impacts applied.